Let's not make invariants const

[Christophe Travert]

"Era Scarecrow" , dans le message (digitalmars.D:174206), a écrit :
>   I would think it does however during verbose output specifying 
> if an invariant or contract is changing data and that may alter 
> behavior.

Signatures in some place should be by default const, pure, nothrow. This 
is the case for invariant() (if you consider it as a function) [1]. 
However, it is only possible to have different default than non-const, 
non-pure, throw, if the langage support a way to remove those default 
attributes. Maybe this should be included in the langage.

-- 
Christophe

[1] Actually, I would rather have a langage where all functions are by 
default const (wrt all parameters, except this), pure, nothrow... But 
it seems D is not that langage and it not going to be.